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JOANNE STUBBE: Hi, everybody.

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You're in 507, and if you
look at your syllabus,

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you'll find one of the things in
the front page of your syllabus

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is called a lexicon.

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And I'd like to
introduce you to why

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we've chosen to have a
lexicon for this course.

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So if you look at this
particular slide or overhead,

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this is what John is
going to teach you

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this semester--
introductory metabolism.

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The glycolysis pathway,
fatty acid biosynthesis,

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fatty acid oxidation,
amino acid metabolism.

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A complete jungle.

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How are we ever going to learn
anything out of this mess?

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Well, that's actually
exactly the point.

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So what we're going to do over
the course of the semester

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is convince you that
all of this mess

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can be simplified to
10 basic reactions.

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And those 10 basic reactions
are what's in the lexicon.

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So it turns out
all of biochemistry

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for primary metabolism
can be described

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using 10 different sets of
reactions and your vitamin

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bottle.

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And so if you look at
your vitamin bottle,

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what do you see?

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Most of you probably
take vitamins.

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You have vitamin B1, vitamin
B2, vitamin B3, vitamin B6,

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vitamin B12.

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All of those provide
enzymes the catalysts

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for all the reactions in this
complex metabolic pathway

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I showed you on
the previous slide.

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They expand the
repertoire of reactions

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that enzymes can
actually catalyze.

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And so within the lexicon,
what we're going to show

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you is the chemistry of actually
how these vitamins work.

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So again, if we come
back to the lexicon,

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we'll talk about how
carbon-carbon bonds are

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made and broken, fatty acid
metabolism, sugar metabolism.

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We'll talk about oxidation
reduction reactions

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and the vitamins that are
used for that transformation.

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We'll talk about the energy
storage and the energy currency

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in the cell-- ATP, etc.

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So what the lexicon
is meant to do

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is be an aid when you
can't remember what

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does oxidation and reduction?

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You can go back to your
lexicon and look up

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what are the redox
cofactors that

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are involved in transformation.

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And by practicing the
chemistry in the first part

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of the semester of
all these reactions,

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metabolism should be
very straightforward

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in terms of all
the connectivities.

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So hopefully what you will do
is look through your lexicon

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tonight, see what
these reactions are,

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and then keep it by your
side during the rest

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of the semester.

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And when you're having
trouble understanding

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some chemical
transformation, you

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can use the lexicon as a guide
to think about the chemical

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transformations that
you'll be looking

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at over the course
of the semester.